A government under the Conservatives would increase the proportion of green taxes, shadow chancellor George Osborne is to promise.
In a renewed effort to challenge Labour's record on the environment, Osborne claims that the total revenue raised from taxes on environmentally unfriendly actions has declined under Tony Blair from 7.7% in 1997 to 6.2% in 2006.
The shadow chancellor, who will make a speech later today in Tokyo detailing the Tory plans, is to promise for the first time that his party will make a manifesto pledge to hike up green taxes.
"I am clear that the proportion of tax revenues drawn from environmental taxes needs to increase," Osborne told the 'Financial Times'.
"We need to go in the opposite direction to the one in which Gordon Brown has been taking the tax system."